There are several types of fruitworms, which are the larvae of different moth species in the genus Lepidoptera. The larvae are pests of fruit trees and usually present as thick green caterpillars. Fruitworms live in their host trees and cause damage to new growth, leaves, flowers, and fruit. The damage is usually discovered when it is too late for fruitworm control. Learn how to control fruitworms to prevent this damage and scarring on your home fruit crop.
Green Worms on Fruit
Gardeners must closely monitor fruit trees to ensure that any number of pests do not infest them. Visual inspections during early to mid-spring may yield green worms on fruit. There is only one generation per year, but the larvae pupate and overwinter in the ground to emerge and feed when tender shoots and buds appear.
The green worms on fruit may be armyworms or climbing cutworms depending on their behavior.
- Armyworms move in large groups to ideal feeding areas and cause widespread damage.
- Cutworms begin feeding on the roots of young plants and migrate to the branches of trees as new shoots appear.
Green fruitworms are the most common, but there are several other types of fruitworms.
Other Types of Fruitworms
Among these pests are numerous types of fruitworms, which are found across the country. In the family Noctuidae, there are also pyramidal and speckled fruitworms. The eggs are a fraction of an inch (2.5 cm.) and the adult moth lays them on the stems and leaves of host trees.
Speckled fruitworms are over an inch (2.5 cm.) long with stripes and dots along the length of the body.
The pyramidal larvae start out cream colored and turn green after the first life cycle. They then sport five strips and a hump on the dorsal end.
The common green fruitworm is a little smaller than the other species and starts out cream, then turns yellow and finally light green.
Damage from Fruitworms
The larvae feed on a variety of deciduous plants and widely infest cherry, pear, and apple trees. Fruitworm feeding does not seriously affect the health of trees, but they can compromise the quality and amount of harvest.
Their feeding activities on buds result in flower drop and any later feeding can cause early abortion of the growing fruit. Fruits that make it to harvest are distorted and have cork-like scars.
Inspection and manual management is generally enough fruitworm control for the gardener with only a few plants.
How to Control Fruitworms
Fruitworm control starts with careful monitoring. You can hand pick the larvae off small trees. Removing the larvae early will prevent later generations. Watch for damage to terminal shoots and bud injury. Small fruits that are forming may have scars and brown scabs, which indicate fruitworm feeding.
Getting rid of fruitworms naturally is preferred on plants with edible crops. You can reduce the population of adults with sticky traps. Bacillus thuringiensis (Bt) has shown to be moderately effective for getting rid of fruitworms naturally. There are other biological controls, such as certain wasps and nematodes, which are only practical in minor infestations.
If the pests consistently plague you, uses an insecticide coded for codling moths and apply at bud stage and again after petal fall.